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101.
Boolean networks are a popular model class for capturing the interactions of genes and global dynamical behavior of genetic regulatory networks. Recently, a significant amount of attention has been focused on the inference or identification of the model structure from gene expression data. We consider the Consistency as well as Best-Fit Extension problems in the context of inferring the networks from data. The latter approach is especially useful in situations when gene expression measurements are noisy and may lead to inconsistent observations. We propose simple efficient algorithms that can be used to answer the Consistency Problem and find one or all consistent Boolean networks relative to the given examples. The same method is extended to learning gene regulatory networks under the Best-Fit Extension paradigm. We also introduce a simple and fast way of finding all Boolean networks having limited error size in the Best-Fit Extension Problem setting. We apply the inference methods to a real gene expression data set and present the results for a selected set of genes.  相似文献   
102.
Objective: Although restrained eating is believed to increase overeating and weight in the long term, the opposite has also been found: Heavy individuals are more likely to diet. The objective of the current study was to test both pathways for adolescents. Design: A longitudinal model was used to explore the bidirectional associations between restrained eating and body mass index (BMI). Main Outcome Measures: At 3 annual waves, restrained eating and BMI were obtained from both older (M age 15.2 years old) and younger (M age 13.4 years old) adolescent boys and girls who were sibling pairs in 404 Dutch families. Results: Structural equation modeling showed that BMI predicted restrained eating more consistently than the other way round. The results remained the same when analyzed by sex, age, socioeconomic status, and overeating tendency. Thus, in our general survey of adolescents restrained eating did not seem to be a successful weight loss strategy, nor did it consistently predict weight increase. Conclusion: Positive associations between restrained eating and BMI should mainly be interpreted in the sense that higher BMI predicted more restrained eating. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
BACKGROUND: Wholegrain food may have an important role in the prevention of chronic diseases, and therefore its consumption should be increased. However, wholegrain products have a low consumption because of unfamiliar taste and poor understanding about the health benefits. Generally, adolescents unfamiliar with wholegrain bread dislike it. Food use in childhood correlates positively with practices in adult life, and therefore adolescents are an important target group for research. The aim was to study adolescents' attitudes towards wholegrain bread in a society where wholegrain products are widely used. RESULTS: A qualitative focus group method (n = 61) and a quantitative procedure (n = 104) with 13–15‐year‐old secondary school students indicated that Finnish adolescents considered wholegrain breads healthier and more acceptable than refined breads. The motives for wholegrain bread consumption were taste, feeling of fillingness and weight control. Girls were more interested in bread healthfulness than boys (P < 0.01), and participants who showed a more positive attitude towards general health interest reported using more rye and wholegrain breads than participants with negative attitudes. CONCLUSION: Adolescents familiar with the sensory properties and healthfulness of rye and wholegrain breads consumed them regularly and perceived them as pleasant and very acceptable. Copyright © 2010 Society of Chemical Industry  相似文献   
104.
The requirements for telecommunication at 2012 are estimated to be on such demanding level that the 3G technologies will not be sufficient. It is unlikely that the 3G Radio Access Network (RAN) would scale up i.e., Fourth Generation (4G) RAN will need to be developed. The requirements for 4G are demanding and the level of uncertainty is high. The novel ad hoc networking technologies could provide flexible solutions for the 4G RAN and extend the operator radio coverage. Combining these differing communication technologies provides insight for the 4G RAN design. This paper analyses the Mobile Ad hoc Networks (MANET) requirements against the 4G requirements in terms of energy conservation. We find that there is mismatch between these two sets of requirements. Nevertheless, we demonstrate how these two approaches could co-exist in a mutually beneficial way. Finally, we propose interoperability requirements for MANET and 4G routing from the perspective of energy conservation. Harri Paloheimo is a researcher in Networking Technologies Laboratory at Nokia Research Center, Helsinki. In addition, he is a post graduate student in Telecommunications Software and Multimedia Laboratory, Department of Computer Science and Engineering, Helsinki University of Technology. He received M.Sc. degree majoring in space technology from Department of Electrical and Communications Engineering, Helsinki University of Technology in 2000. He currently works on next generation wireless networks with special interest in hybrid and relay networking solutions. Sudhir Dixit is currently a Nokia Research Fellow and works on next generation wireless networks. From 1996 to 2003 he was a Senior Research Manager, focusing on IP/ATM, wireless, content networks, and optical networks. Prior to that he worked at NYNEX Science & Technology (now Verizon), GTE (now Verizon), Codex Motorola, Wang, Harris, and STL (now Nortel Europe Labs). He has published or presented over 150 papers, published three books, and holds 14 patents. He is on the Editorial Board of the IEEE Communications Magazine, Springer's Wireless Personal Communications Journal, and KIC's Journal of Communications and Networks. He received a B.E. degree from MANIT, Bhopal, India, an M.E. degree from BITS, Pilani, India, a Ph.D. degree from the University of Strathclyde, Glasgow, Scotland, and an M.B.A. degree from Florida Institute of Technology, Melbourne. He is a Fellow of IEE (UK) and IETE (India). He represents Nokia on the Steering Board of the Wireless World Research Forum, and is also Vice Chair of the SIG on Self-Organization of Wireless World Systems. Dr.Tech. Antti Ylä-Jääski is a Professor of Telecommunications Software, Telecommunications Software and Multimedia Laboratory, Department of Computer Science and Engineering, Helsinki University of Technology. He is also a Research Fellow in Network Technologies Laboratory, Nokia Research Center, Helsinki. Prof Dr.Tech. Antti Ylä-Jääski received his PhD in ETH Zuerich 1993. Antti has worked with Nokia 1994–2004 in several research management positions with focus on future Internet technologies, mobile networks, applications, services, service management and service architectures. He has published about 30 articles and he holds several approved patents. Antti's current research interests include mobile networking, heterogeneous network environments, services, service architectures, service management and security issues.  相似文献   
105.
106.
Organizations, which consider investment in or divestment of power production licences/capacity within the European Community, are exposed to the impacts of the European Union Emission allowance Trading Scheme (EU ETS). In this paper, the consequences of the EU ETS on investment decisions are explored in a country-specific setting in Finland. First, we review the general mechanisms through which the EU ETS influences size, timing and cashflows of an investment. Next, we discuss the projected changes in Finnish power producers’ investment environment and examine the financial impacts due to the EU ETS on a case investment decision, a hypothetical condensing power plant (250 MWe). The standard discounted cash flow (DCF) analysis is extended to take into account the value of two real options: the option to wait and the option to alter operating scale. In a quantitative investment appraisal, the impact of emissions trading not only depends on the expected level of allowance prices, but also on their volatility and correlation with electricity and fuel prices. The case study shows that the uncertainty regarding the allocation of emission allowances is critical in a quantitative investment appraisal of fossil fuel-fired power plants.  相似文献   
107.
2,6-Bis(1,4,7,10-tetraazacyclododecan-1-ylmethyl)pyridine (11a) and 1,3-bis(1,4,7,10-tetraazacyclododecan-1-ylmethyl)benzene (11b) have been shown to accelerate at 50 mmol·L−1 concentration both the cleavage and mutual isomerization of uridylyl-3′,5′-uridine and uridylyl-2′,5′-uridine by up to two orders of magnitude. The catalytically active ionic forms are the tri- (in the case of 11b) tetra- and pentacations. The pyridine nitrogen is not critical for efficient catalysis, since the activity of 11b is even slightly higher than that of 11a. On the other hand, protonation of the pyridine nitrogen still makes 11a approximately four times more efficient as a catalyst, but only for the cleavage reaction. Interestingly, the respective reactions of adenylyl-3′,5′-adenosine were not accelerated, suggesting that the catalysis is base moiety selective.  相似文献   
108.
109.
The link level performance and the cellular systemcapacity in the uplink direction of a CDMA cellularsystem utilising multiuser detection base stationreceivers is analysed by simulation. In the receiver,parallel multistage multiuser detection is employedtogether with two-antenna diversity reception and fastclosed-loop power control. A system level simulator isbuilt to utilise the link level simulation results andto show the increase in cellular capacity obtained byusing multiuser detection. The capacity is studied inurban micro and macro-cell environments utilising thechannel models developed in the European CODITproject. The modelling of the environment specific andCDMA specific features is considered in the systemsimulator. The system level simulator is calibratedwith analytical capacity calculations.  相似文献   
110.
The objective of this work is to study the influence of effective initial impingement drying (one-sided high intensity air impingement drying) on the quality of blade-coated paper and to compare it with IR (infrared) drying. A specially designed 1.31 m-long impingement air dryer unit was installed 2 m downstream of the coating station of the pilot coater for more efficient paper drying. Different drying strategies using different combinations of three impingement temperatures (300, 450 and 550 °C) and three impingement velocities (25, 40 and 60 m/s) were tested in the impingement dryer unit to determine the influence of drying on paper quality. Drying effects are compared with those obtained with two rows of an electrical IR at same position. The results of the investigation indicate that backtrap (BT) mottle was reduced with increasing drying power of the impingement dryer. The paper quality parameters, gloss and smoothness of the coated samples were better with air-drying than IR drying. The interesting finding of this study is the improvement of mottle with a high drying rate in the consolidation phase for coated WF (wood-free) paper. Drying section configuration with effective impingement drying unit directly after the coating station showed good performance and is proposed as a possible solution for the future dryer designs.  相似文献   
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